It has been a while since I was able to update my 4.2 engine experiences. Sorry it took so long but we had some other problems that could not wait. But first, I want to extend my heartfelt thanks to all those so very kind to reply with advice and suggestions. They all helped and are very much appreciated. Currently, the engine has been completely and totally disassembled to the last tiny screw. The block was completely bare. Nothing remained in it. The factory original crank had 3-4 very light and thin grooves on the #1 rod journal that you could barely detect with a fingernail. They were so light I thought they could just be polished out. But, the engine shop I initially went to with the block and crank, recommended I replace the crank. In retrospect, I may have been taken advantage of with them selling me a reground crank instead of just polishing or regrinding only the #1 rod journal. No bearings had spun and all the other journals were in excellent shape. The tapping noise we heard when the egnine was running came from the bottom of the pin boss for the #1 piston, hitting the crank counterweight each time it came around. The bent rod made the overall length shorter, pulling the piston closer to the crank. The piston had some dime size scuffing on the pin boss with no other damage evident.
The water pump studs that go through the timing chain cover snapped off inside the timing cover when I tried to remove the water pump even though I used heat and tried tapping them first to shock any corrosion loose. The water pump eventually came off but had to be replaced. The bolt/stud holes in the timing cover and water pump, were filled with corrosion from reaction between the metal studs/bolts and the aluminum where coolant had seeped in and they simply would not loosen. They all broke off inside the timing cover and the timing cover also had to be replaced. Brand new replacement parts include a timing chain, two timing gears, the timing chain tensioner, oil pump, timing chain cover, water pump, and a crankshaft sensor when that snapped in half trying to remove it from the old cover, ring set, bearing set, gasket sets, and some other miscelleanous items. Today I took all the rods and piston assemblies to an AERA member shop, and had them measured. After torquing the rod caps, three of the rods have bearing journals .001" to .0015" past the 2.4724 maximum, when measured in the same line as the long axis of the rod where the load is maximized. Measuring horizontally, across the cracked joints for the rod cap, they were all within tolerance. So, now I might need three replacement reconditioned rods and two others that were in tolerance might need reconditioning to be perfectly round, with only the #6 rod perfectly round and within tolerance. I had purchased a new piston assembly and a reconditioned rod for a little over $100 to replace the bent #1rod, but guess what? The new replacement rod is the worst of all of them in exceeding tolerance on the veertical axis and is .0015" out of round. That was a surprise and it will need to be replaced. All the pistons appear to be reusable. The block has had all rust deposits removed, was solvent washed, and then washed with hot water and Tide, and thoroguhly rinsed and sprayed with light oil. Then all cylinders and lifter bores were repeatedly wiped with white towels soaked in light oil until they came out perfectly clean. This took a while. To install the new crank, Lubriplate was wiped onto all crank bearings, and the crank main journals, and the crank installed into the block. Extreme care was taken to avoid any scratches to journal and bearing surfaces.
One thing I am wondering about is this - the engine ran fine before. In fact, it ran beautifully, was smooth, and quiet. During inspection I found that all the other bearings showed high wear rates, with some of them having worn through their babbitt and showing copper, making me wonder about the vehicle mileage, or it's care. But, because it ran so well and expenses are mounting I am wondering how bad would it be to reuse the existing rods with new bearings. The bearing clearances had to be pretty large with all the previous wear we found, the rods were just as much out of tolerance and out of round as they are now, and yet the engine was using absolutely no oil, ran smoothly, and gave decent fuel mileage. Would it really be that bad to reuse the rods? This van is not used daily. It is used maybe 1-2 days per week and I would be surprised if it accumulates more than 7000-8000 miles per year. The heads are flat and the intake manifold will be checked next week. The opinons I have from AERA members who have looked at the block and other parts is that the previous owner failed to flush his coolant every year or two and the acids from it, along with normal thermal cycling, degraded the head and/or intake gaskets until they failed at the #1 cylinder and allowed coolant to leak into #1 cylinder. When it was driven daily this was not a problem because the leak was so slow the coolant was all blown out at startup the next day. But when I let it sit for five days, with the #1 piston near top dead center, enough coolant leaked into the cylinder to hydrolock it at startup and that bent the rod. No other cause has been found. The block has not been magnafluxed or pressure tested because the engine shop that did the initial inspection did not think it was warranted. Even though they grind crankshafts, they recommended replacing the crank, whcih I did.
But now, faced with another $500 in expenses and a very upset wife (not kidding here), I have to ask, would it really be that bad to reuse the existing rods in their existing condition, with new bearings throughout? It has to be better than it was. The three worst rods measure 2.4285 on the vertical axis. The others are all at 2.4270 or 2.4275. The high end of the Ford tolerance for connecting rods is 2.4274 or 2.4275 depending on which source you use. So, the worst rods are just .001 out of tolerance and .001" out of round. That is only .0005" per bearing.
Any opinions or suggestions will again be truly appreciated.
And so it goes.